A surface at a particular voltage level, referred to as a xe2x80x9cpower plane,xe2x80x9d can distribute power in a Printed Circuit Board (PCB) or an Integrated Circuit (IC). Similarly, a ground plane can distribute ground in a PCB or an IC. As system bandwidth increases (e.g., in a system associated with high frequency signals), effective power and ground distribution becomes more important. In particular, reducing noise inference between power planes and/or ground planes may enable operation at a higher system bandwidths.
One example of a power plane is a power bus (VTT) that distributes power to components. In this case, a termination resistor (RTT) can be provided to reduce noise interference (e.g., signal reflection) in order to improve voltage fluxuation, flight time variation, and noise margins. Moreover, it is known that interference between power planes can be reduced using decoupling capacitors.
For example, FIG. 1 illustrates the performance of a typical decoupling capacitor (e.g., having an equivalent circuit model 110). Note that once the frequency of a signal rises past a certain level (e.g., a frequency level associated with series resonance), the decoupling capacitors become less effective (i.e., the amount of noise interference 120 increases). As a result, the system bandwidth may be limited. In the case of ground planes, similar problems may cause Electro-Static Discharge (ESD) and ground bounce noise interference problems.